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Intravital Video Microscopy Measurements of Retinal Blood Flow in Mice
Published on: December 26, 2013
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Mapping flow velocity in the human retinal capillary network with pixel intensity cross correlation
Phillip Bedggood1, Andrew Metha1
1Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, Australia.
Plos One
|June 26, 2019
Summary
We developed a new method, pixel intensity cross-correlation (PIX), to measure cellular velocity in retinal blood vessels. PIX offers improved resolution and accuracy compared to existing techniques.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Fluid Dynamics
Background:
- Accurate measurement of cellular velocity in retinal vasculature is crucial for understanding ocular health.
- Existing methods for velocimetry in retinal microvasculature have limitations in spatial and temporal resolution.
Purpose of the Study:
- To introduce and validate a novel algorithm, pixel intensity cross-correlation (PIX), for determining cellular velocity in retinal vascular networks.
- To compare the performance of PIX against established velocimetry techniques and manual tracking.
Main Methods:
- The PIX method compares pixel intensity profiles across time-shifted video frames to identify flow information.
- Velocity is calculated based on spatial displacement and inter-frame time.
- Adaptive optics imaging was used to visualize the smallest retinal vascular networks.
Main Results:
- PIX demonstrated potential for enhanced spatial and temporal resolution in cellular velocity measurements.
- The algorithm showed improved resilience to noise and aliasing compared to particle image velocimetry and spatiotemporal kymograph.
- PIX provided a robust assessment of retinal network flow properties.
Conclusions:
- Pixel intensity cross-correlation (PIX) represents a significant advancement in measuring cellular velocity within retinal microvasculature.
- The method offers superior performance characteristics, paving the way for more precise analysis of retinal blood flow.
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